XU Xinyi, GU Shaoxuan, XIA Suqi, GU Anna
(School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, Hubei, China)
Abstract: The powders of CaO-MgO-Al2O3-B2O3-SiO2 system glass with varied B2O3 content were prepared by a sol-combustion method. The resulted powders exhibited an amorphous nature and uniform particle morphology, with the mean particle sizes around 80 nm. The structure and crystallization behavior of the powders were investigated as a function of B2O3 content by employing XRD, FT-IR and DTA methods. The addition of B2O3 led to coexistence of [SiO4] tetrahedral network and [BO3] triangle chains as the structural frameworks, producing a tighter glass structure while enhancing static electric interactions between the anion structural units and network-modifying cations such as Ca2+ and Mg2+. As a result, the transition temperature Tg of the glass system was significantly decreased due to the addition of B2O3. Meanwhile, the crystallization ability of the glass powders at elevated temperatures was effectively suppressed. The borosilicate glass powders basically maintained an amorphous structure after calcining at 1150 ℃.
Key words: borosilicate glass system; alkali-free; sintering aids; structure; crystallization ability